Companies and other organizations rely upon mobile stations for their employees to remain accessible regardless of their location. A mobile station can be any type of wireless communication device including wireless telephones, wireless Personal Digital Assistants (PDA), wireless pagers, or any device which performs one or more of these functions. This accessibility applies to both travel away from the company's office and the ability to communicate within the office. While in the office employees may use a mobile station to receive telephone calls or electronic mail when they are not near their desktop telephone or computer.
Increased usage of wireless communications by companies has resulted in increasing bills for such wireless communications. To reduce costs for wireless communications which originate or terminate within a company's premises, some companies have installed private wireless networks to avoid paying wireless carriers for airtime for such communications. These private wireless networks typically are independent of wireless service providers' macro networks, expensive to implement, and do not provide a number of features which would be desired by businesses.
Some private wireless networks operate using communication protocols which are not typically employed by major wireless carriers on their macro networks. For example, some companies have attempted to implement private wireless networks which operate using Voice over wireless Internet Protocol (IP). While one advantage of using wireless protocols which are not compatible with protocols used by major wireless carriers is that the company does not have to be concerned with receiving charges for airtime usage on wireless macro networks, the use of incompatible protocols reduces the flexibility provided to the business. Specifically, if an employee is authorized to communicate within both a private wireless network and wireless macro network, the employee would be required to have two different mobile stations, each with a different telephone number. This is particularly inconvenient as such an arrangement requires the employee to carry two mobile stations while within the company's premises so that calls to either telephone number can be received. Additionally, this may result in the employee having two separate voicemail systems, one for each wireless network. Moreover, if an employee initiates a telephone call within the private wireless network and travels to an area outside of the private wireless network, the employee's telephone call will be dropped because the mobile station does not use the same protocols as wireless macro networks.
Accordingly, there is a need for a system and method of providing wireless communications over both publicly-accessible and private wireless networks.